JP3258598B2 - Gas turbine air separator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine air separator, and more particularly to a gas turbine air separator having a structure capable of preventing occurrence of cracks at an end of the air separator.

[0002]

2. Description of the Related Art An air separator is a device for guiding and taking in rotor and blade cooling air from a compressor. FIG. 4 is a sectional view and FIG. 5 is a perspective view. In FIG.
Reference numeral 1 denotes a rotor, and reference numeral 2 denotes a single-stage rotor blade attached to the rotor 1 via a disk unit 7, and rotates together with the rotor 1. Reference numeral 3 denotes a one-stage stationary blade, and reference numeral 4 denotes a seal ring holding ring inside the stationary blade 3. Reference numeral 5 denotes a duct for guiding cooling air 30 from the compressor to the space 6. Reference numeral 7 denotes a disk portion to which the blade root of the rotor blade 2 is attached, and 8 denotes a bolt and a nut.
Reference numerals 41 and 42 denote fixed-side seal portions, and reference numeral 43 denotes an air supply hole for sending cooling air to the rear stage of the disk 7.

[0003] Reference numeral 10 denotes an air separator which has a cylindrical shape surrounding the periphery of the rotor 1, has a flange portion 13 at the left end, and has a bolt hole 9 formed therein.
Is mounted on the base with bolts and nuts 8. The right end has a flange portion 12, and the periphery of the tip portion is in contact with the disk portion 7. An air hole 1 is provided at the center of the air separator 10.
1 is provided in the periphery, and the cooling air 30 from the space 6 is supplied to a passage 31 formed between the rotor 1 and the inner periphery of the air separator.
To the air supply hole 43 of the disk 7 and also to the radial hole 44 for guiding cooling air from the disk portion 7 to the first stage blade 2. In addition, the outer periphery of the air separator 10 is close to the fixed-side seal portions 41 and 42 to prevent the cooling air from leaking to the outside via the seal fins.

FIG. 5 is a perspective view of an air separator 10 which has a cylindrical shape surrounding the periphery of the rotor 1 and has a large number of air holes 11 around the center as described above. Have flange portions 12 and 13 and the flange portion 1
Reference numeral 3 denotes a structure which is attached to the rotor 1 with bolts and nuts through bolt holes 9.

FIG. 6 shows a flange portion on the moving blade side of the air separator, (a) is a sectional view of a contact portion on the moving blade side, and (b)
FIG. 4 is a perspective view showing a state where a crack has occurred in a flange portion. As shown in FIG. 6 (a), the periphery of the distal end of the flange portion 12 comes into contact with the disk portion 7 of the rotor and is lightly pressed to maintain a constant surface pressure with the disk side.

As described above, the air separator 10 has an overbank structure which is fixed to the rotor 1 by the bolts and nuts 8 by the flange 13 at one end, and the flange 12 at the other end has a constant surface pressure on the disk side. As shown in FIG. 6B, cracks may occur in the flange portion 12 which comes into contact with the rotor 1 and rotates together with the rotor 1 and repeatedly contacts with the disk 7 when hot restart is repeated.

[0007] The cause is that the air separator 10 is restarted in a hot state within several hours of stoppage, cool cooling air flows, and when cooled, the air separator 10 is rapidly cooled, and the pressing force of the flange portion 12 against the disk 7 decreases. . By operating in a state where the pressing force is reduced, relative slippage occurs between the flange portion 12 and the disk contact side, the surface is roughened, and fine cracks are generated due to local stress. And a crack portion is opened, and this portion is turned up by centrifugal force, resulting in a crack as shown in FIG.

[0008]

As described above, the conventional gas turbine air separator has an overbank structure in which a flange portion 13 at one end is fastened to a rotor side by bolts and nuts 8, and a flange portion 12 at the other end is formed. It is in contact with the disk side of the first stage rotor blade at a constant surface pressure, rotates together with the rotor 1, and cools the cooling air 30 from the compressor into a space 3 with the rotor side.
1 to the air supply hole 43 and the radial hole 44 on the disk 7 side. Therefore, when hot restart is repeated, relative slippage occurs between the flange portion 12 and the disk side as described above, and the fretting fatigue causes cracks in the flange portion 12 to cause damage.

In view of the above, the present invention has been made to prevent the occurrence of cracks in the air separator flange by changing the structure of the air separator, eliminating the contact portion with the disk side, and eliminating relative slip at the contact portion. An object of the present invention is to provide a gas turbine air separator having a simple structure.

[0010]

The present invention provides the following means for solving the above-mentioned problems.

The front and rear cylindrical members are divided into two parts at predetermined intervals in the axial direction of the rotor and are disposed around the rotor. The front cylindrical member is in close contact with the periphery of the rotor and the outer periphery is fixed. The rear cylindrical member holds a space around the rotor communicating with the space, and fixes the tip to the disk portion on the one-stage moving blade side, and the outer periphery forms a fixed side and a seal portion. A gas turbine air separator, wherein cooling air is supplied from a space around the rotor of the rear cylindrical member to a disk portion on the first stage blade side.

The air separator of the present invention is composed of a cylindrical member divided into two parts. Each cylindrical member is fixed to the disk on the rotor side and the one-stage moving blade side. The cooling air is guided, passes through the space between the rear cylindrical member and the periphery of the rotor, and is supplied to the disk portion on the one-stage moving blade side. Each of the cylindrical members is independently fixed, and the outer peripheral portion thereof constitutes a fixed side and a seal portion, thereby preventing the cooling air from leaking to the outside. Therefore, unlike the overbank structure in which only the front end is fixed to the rotor side and the other rear end is fixed to the disk side as in the conventional air separator, the restarting is repeated because the contact portion with the disk part is eliminated. However, there is no portion where the contact portion is rubbed due to thermal stress, and no crack is generated in the flange portion due to fretting fatigue.

[0013]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a sectional view of a gas turbine air separator according to one embodiment of the present invention. In the figure, 1 is a rotor, 2 is a rotor 1
Is a one-stage moving blade attached to the rotor 1 via a disk 7, and rotates together with the rotor 1. Reference numeral 3 denotes a one-stage stationary blade, and reference numeral 4 denotes a seal ring holding ring inside the stationary blade 3. Reference numeral 5 denotes a duct for sending cooling air 30 from the compressor to the space 6. Reference numeral 7 denotes the above-described disk portion, and reference numeral 8 denotes a bolt / nut. 41 and 42 are fixed-side seal portions; 43 is an air supply hole for sending cooling air to a subsequent stage;
Reference numeral 4 denotes a radial hole, and the above configuration is the same as that of the conventional example shown in FIG.

Reference numeral 20 denotes an air separator of the present embodiment, which has a cylindrical shape and has a structure divided into 20-1 and 20-2. Reference numeral 20-1 has a flange portion 21 at an end, and is attached to the rotor 1 by tightening with a bolt and nut 8, and rotates together with the rotor 1. This separator 20-1
Is for preventing the cooling air 30 from leaking out of the space 6.

The reference numeral 20-2 is arranged so as to keep a predetermined interval 33 from the reference numeral 20-1 and to keep a constant gap 32 with the rotor 1 side, and has a flange portion 22 at one end. Is provided with a bolt hole 23, is attached to the disk side 7 by a bolt 28 through the hole 23, and rotates together with the rotor 1.

As described above, the air separator 20 is
-1 and 20-2, 20-1 and 20-2 rotate together with the rotor 1 and pass through the central divided space 33, the cooling air 30 flows in from the space 6, and passes through the passage 32. Air supply hole 43 and radial hole 4 of disk 7
4 is supplied with cooling air. Further, the outer circumferences of 20-1 and 20-2 are close to the fixed-side seal portions 41 and 42, and constitute a seal portion to prevent leakage of cooling air from the outer circumference to the outside.

FIG. 2 is a perspective view of the air separator 20, which has a two-part structure of 20-1 and 20-2.
It has a cylindrical shape surrounding. One end of 20-1 has a flange portion 21, and a bolt hole 24 is formed around the flange portion to be connected to the disk portion. The other end of 20-1 is 2
0-2 and at a fixed distance from each other.
0-2 has a flange portion 22 at the other end.
2 has a bolt hole 23 to be attached to the disk portion on the first stage blade side.

FIG. 3 is a cross-sectional view showing a state where the flange portion 22 of the air separator 20-2 is mounted.
A bolt 8 is passed through the bolt hole 23 of the first stage, and the entire circumference is attached to the disk 7 on the one-stage moving blade 2 side.

The air separator 2 of the embodiment having the above configuration
Numeral 0 denotes a two-part structure of 20-1 and 20-2, in which cooling air 30 from the compressor enters the space 6 through the duct 5, flows into the space 33 from the space 6, and is connected to the rotor 1 side and the air separator 20-. 2 through the passage 32 formed by the disk 7,
The air is supplied to the air supply hole 43 and the radial hole 44.
Further, the outer periphery of the air separator 20-1 forms a seal portion with one fixed side seal portion 42, and the outer periphery of the air separator 20-2 forms a seal portion with the other fixed side seal portion 41, respectively.
Cooling air is prevented from leaking to the outside.

As described above, in the present embodiment,
The air separator 20 has a structure in which 20-1 is fixed to the rotor side by bolts 8 and 20-2 is fixed to the disk side by bolts 28, and rotates together with the rotor 1.
Unlike a conventional overbank structure in which only one end is bolted and the other end abuts on the one-stage rotor blade 2 side, the rotor 1 side has no contact portion and the flange portions 21 and 22 are bolted together. Therefore, occurrence of cracks due to fretting fatigue of the flange portion is prevented.

[0021]

The present invention comprises a front and rear cylindrical member which is divided into two parts at predetermined intervals in the longitudinal direction of the rotor and which is disposed around the rotor. And the outer periphery constitutes a seal portion with the stationary side; the rear cylindrical member holds a space around the rotor communicating with the space, and the distal end is fixed to the disk portion on the one-stage blade side and the outer periphery is fixed. The cooling air is supplied from the space around the rotor of the rear cylindrical member to the disk portion on the first stage blade side. With such a configuration, the conventional overbank structure is avoided, and the flange portions of the divided members are fixed, so that there is no contact portion, and the occurrence of cracks in the flange portion due to fretting fatigue is prevented. Therefore, the reliability of the gas turbine is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a gas turbine air separator according to one embodiment of the present invention.

FIG. 2 is a perspective view of an air separator according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view of a mounting portion on a moving blade side of the gas turbine air separator according to one embodiment of the present invention.

FIG. 4 is a sectional view of a conventional gas turbine air separator.

FIG. 5 is a perspective view of a conventional gas turbine air separator.

6A and 6B show a rotor blade side contact portion of a conventional gas turbine air separator, wherein FIG. 6A is a cross-sectional view, and FIG. 6B is a perspective view showing a state in which cracks occur in a flange portion thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor 2 Moving blade 5 Duct 6 Space 7 Disk part 8 Bolt and nut 20 Air separator 21, 22 Flange part 23, 24 Bolt hole 28 Bolt 32 Passage 33 Interval 43 Air supply hole 44 Radial hole

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kiyoshi Suenaga 2-1-1, Shinhama, Arai-machi, Takasago-shi, Hyogo Mitsubishi Heavy Industries, Ltd. Takasago Machinery Works (56) References JP-A-8-284687 (JP, A) JP-A-8-177526 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F01D 5/08 F01D 11/02 F02C 7/18

Claims (1)

(57) [Claims] 1. A method in which a predetermined distance is maintained between front and rear directions in the rotor axis direction.
The front cylindrical member is divided and disposed around the rotor, and the front cylindrical member is in close contact with the periphery of the rotor and the outer periphery forms a fixed side and a seal portion; and the rear cylindrical member is The space surrounding the rotor communicating with the space is held, and the tip is fixed to the disk portion on the one-stage moving blade side, and the outer periphery is arranged so as to form a seal portion with the fixed side; A gas turbine air separator characterized in that cooling air is supplied from a space around a rotor to a disk portion on the first stage blade side.